Socket for electron tubes



July 13, 1965 Filed April 50, 1962 A. M. CAMPO ETAL SOCKET FOR ELECTRON TUBES 2 Sheets-Sheet 1 INVENTORS AUGUSTINE M. CAMPO JERZY SZKUP July 13, 1965 A. M. CAMPO ETAL 3,195,096

SOCKET FOR ELECTRON TUBES Filed April 30, 1962 2 Sheets-Sheet 2 IN VEN T ORS AUGUSTINE M. CAMPO J E R2 Y 52 K UP United States Patent 3,195,096 SUCKET FOR ELECTRON TUBES Augustine M. Campo, au Mateo, and jerzy Szkup, San Bruno, Calili, assignors to Eitel-ldctluiiough, Inc, San Carlos, Caiii, a corporation of California Filed Apr. 39, 19-62, Ser. No. 1%,232 tllaims. (El. 33931) This invention relates to sockets for electron tubes and more particularly to sockets of the type adapted to receive electron tubes having terminal pins projecting from one end of the tube. This type of socket will be hereinafter referred to as a pin-type socket.

Pin-type sockets were among the first types of sockets designed during the early stages of the development of electron tubes. However, socket development has lagged behind tube development in some respects, and there has long been a need for an improved pin-type socket. The general object of this invention is to fill that need.

One of the more specific objects of the invention is to provide a pin-type socket which is relatively inexpensive and yet capable of meeting high standards of electrical performance and mechanical strength.

Another object is to provide a socket having an improved design for permitting etficient cooling of a tube.

A further object is to provide a socket which is easily adaptable for use with tubes having different numbers, sizes, and arrangements of terminal pins.

An additional object is to provide a socket in which electrical contact to the contact clips in the socket can be made either to external terminal posts on the socket or by way of short path leads directly to the clips in the socket.

Another object of the invention is to provide a socket in which the contact clips can be easily inserted and removed.

A further object of the invention is to provide a socket in which the contact clips are slightly movable within limits relative to the socket to accommodate tubes having slightly distorted terminal pins.

By way of brief description, the socket of this invention 7 is so constructed that only two difierent members need be manufactured to assemble a complete socket. of these members is a tubular body which can be inexpensively made as a one-piece shefl. T he other member is a one-piece contact clip which is made in the desired number for each socket. The various objects of the invention are obtained by the specific individual and cooperating features of the shell and contact clips, as will be hereinafter described in detail.

Other and further objects and features of advantage will be apparent from the following detailed description which makes reference to the accompanying drawings, in which:

FIGURE 1 is a top view of a socket according to the invention adapted for use with an electron tube having five terminal pins,

FIGURE 2 is a bottom view of the socket of FIG- URE 1,

FIGURE 3 is a side view of the socket of FIGURE 1,

FIGURE 4 is a cross-sectional view taken on the line 44 in FIGURE 1,

FIGURE 5 is an enlarged top view of one of the contact clips shown in FIGURE 1,

FIGURE 6 is a side view of the contact clip of FIG- URE 5,

FIGURE 7 is a front view of the contact clip of FIG- URE 5,

FIGURE 8 is a top plan view of a socket similar to FIGURE 1 but showing the socket adapted for use with an electron tube having four instead of five contact pins "ice and in which the pins are arranged on a smaller diameter circle and in which the pins have smaller individual diameter, and

FIGURE 9 is a side view similar to FIGURE 3 but partly in cross-section and showing a slightly modified construction.

Referring in more detail to FIGURES 14, the socket comprises a shell 1 and a plurality of contact clips 2. These are the only two parts which must be manufactured in order to make the socket.

The shell l is made of any suitable dielectric material which can be formed in a mold; for example, diallyl phthalate plastic is a suitable material for the shell. As seen best in FIGURES 3 and 4, shell 1 comprises a generally tubular structure having a small diameter wall 3 at one end and a larger diameter wall 4 at the other end. I he small diameter wall has an annular internal recess 5 for a purpose to be hereinafter explained. An annular step 6 connects wall portions 3 and 4. ,Step 6 forms a shoulder 7 inside the shell. A plurality of rectangular projections 8-13 project upwardly from shoulder 7 toward the large diameter end of the shell.

The large diameter wall 4 carries a mounting rim 16 having wings 17 with bolt holes 18. In practice the socket is normally mounted on a chassis (not shown) which is apertured to receive the large wall 4. Rim 16 then rests on the chassis and is attached thereto by bolts through holes 18.

A slot 19 is located in the step 6 adjacent the radially outer edge of each of the projections 8-13. It will be noted that the presence of step 6 makes it possible to form the slots 1k in a simple two-piece mold (not shown) which makes the shell 1. Thus, the mold can be a twoiece structure which forms a cavity having the shape of shell 1 (FIGURE 4), with the two pieces of the mold being separable by movement along a line parallel to the axis of the shell. Since the two pieces of the mold are separated by moving them in the direction of the axis of the socket, it is obvious that slots 19 are easily formed by vertical projections on the mold. It can be appreciated that if slots 15? were in a side wall of the shell it would not be practical to form the slots at the same time the shell is molded. Similarly, the shell is provided with slots 26 which can be formed at the same time the shell is molded. There is one slot 20 located adjacent each of the rojections 8-13. The reasons slots 20 can be formed during molding are that they are located at the junction of wall 4 and rim l6, and that rim 16 has a recess 21 communicating with each of the slots 20. Thus, slots 2% and recesses 21 can be formed by vertical projections on the mold.

The contact clips 2 can be made of any electrically conductive spring material such as beryllium copper. As shown best in FIGURES 5-7, each of the contact clips is made in one piece comprising a body strip 25, a pair of support arms 26 and a back tab 27. Each of the arms as carries a contoured wall structure 28, and these walls Zd cooperate to form a slot 29 for receiving a terminal pin on an electron tube. The body strip is provided with a punched-out locking tab 3t which is deformable to release the clip from the socket. An aperture 31 is provided at the end of each body strip to facilitate attachment of an electrical lead to the body strip.

Assembly of the clips in the socket is simply a matter of ushing the body strip 25 down through one of the slots 19 with arms 26 straddling one of the projections 3-13. The downward movement of the clip is continued until locking tab 30 springs out and engages the bottom surface of step 6. In order to remove a clip 2 from the socket it is simply necessary to deform tab 30 out of con tact with step 6 and lift the clip out of the socket.

Occasionally, the terminal pins on electron tubes become bent so that not all the pins on a tube are perfectly aligned with the pin receiving slots in all of the contact clips 2; If the contact clips are rigidly mounted and a tube with bent-pins is forcibly inserted, it can result in damage to the tube. Accordingly, the contact clips 2 are not rigidly mounted in the. shell 1. Instead, the clips are mounted so that they will move slightly in any direction in a plane'passing through all of the clips at right angles to the axis of the shell. This movement is made possible by providing a slight clearance of about .015 inch between each of the arms 26 and the sides of the associated projections 8-13. Similarly, there is a clearance of about -.0O5 inch between the body strip 25 and the radially outer wall of the associated projections 8-13. In addition, there is a clearance of about .005 inch between the back tab 27 and the inner surface of wall 4. Further, the slots 19 are slightly oversized for the body strips 25. As a result of these clearances, the clips are slightly movable in the mentioned plane and yet are securely locked against vertical movement. Vertical movement is prevented by the fact that the bottom edges of arms 26 abut shoulder .7 and the locking tabs 30 abut the bottom surface of step 6.

' It will be noted that since the body strip 25 of each clip projects through the annular step 6, the lower portion of each strip is outside of the socket and forms a convenient external terminal post. Thus, an electrical lead can be looped through aperture 31 and permanently soldered to each of the body strips 25. Sometimes it is desirable to ground one of the socket clips to the surrounding chassis (not shown) and normally it its desirable to do this with the shortest possible electrical lead. Apertures 26 permit this short-lead connection. Thus, instead of connecting the lead to the external portion of body strip 25, the lead can pass directly through aperture 20 in the side of shell 1 and be soldered to the back tab 27 on the clip or clips which are to be grounded to the socket.

The socket has excellent cooling flow characteristics because it is completely open at both ends and because the mounting arrangements for the contact clips do not project. into the path of cooling air through the socket. Cooling air is normally forced upward through the socket and this can be done in; either of two ways. One way is to pressurize the inside of the'chassis (not shown). Since rim 16 of the socket fits tightly against the upper wall of the chassis, the only exit for the high pressure air in the chassis is through the socket. Thus, the presence of slots 29 does not dilute the air flow through the socket because air in the chassis will enter the socket through slots 20 in addition to entering through the open end .3.

The other way of forcing cooling air through the socket is to connect a conduit from a blower (not shown) directly to the open end 3 of the socket. The conduit can be connected to the socket either by slipping the conduit over the outer periphery of end 3 or inserting a smaller conduit inside end 3. Recess 5 is provided so that an inside on the mold so that instead of forming slots 20 they form thin-wall areas 20'. If a short lead connection is required for one or more of the clips 2, it is a simple matter to remove the punch-out area as with the end of a screw driver. a The electrical lead which is passed through the punched-out area will substantially close the opening.

Different types of electron tubes employ different arrangements for their terminal pins. Some tubes have five terminal pins and some have only four pins. In addition, the diameter of each pin in some tubes is less than the diameter of each pin in other tubes. Further, the diameter of the circle on which the pins lie is different for various tubes. The socket of this invention is easily adaptable to accommodate these various differences in terminal pin configurations. For example, FIGURE 8 shows a socket having exactly the same shell 1 as in FIG- URES l4, but adapted to accommodate a tube which, as distinguished from the tube of FIGURES 1-4, has fewer terminal pins, smaller diameter pins, and pins arranged on a smaller pin circle. The only difference in structure which provides this substantial difierence in function between FIGURES 1 and 8 is the structure and arrangement of contact clips 2'. Contact clips 2 have the same body strip 25' and the same back tab 27 .as clips 2. However, clips 2 have longer support arms 26, to accommodate a smaller pin circle. Also, clips .2 have smaller contoured wall structure 28' forming a smaller pin receiving slot 29 to accommodate terminal pins of smaller individual diameter.

It will be noted that the projections 84.3 are the same in FIGURES land 4. There are six projections in all, with four projections 8, 9, 11 and 13 arranged at to each other. are spaced on opposite sides of projection 11 and closer to'projection 11 than to any of the other projections. Thus, it is a simple matter to accommodate a standard five-pin tube by mounting five contact clips on projections 8, 9, 1 12 and 13, as in FIGURE 1, or to accommodate a standard four-pin type tube by mounting four contact clips onprojections 8, 9, 11 and 13, as in FIGURE 8.

Having thus described the invention, what is claimed I as new and desired to be secured by Letters Patent is:

' diameter end and an annular shoulder intermediate said ends, six circumferentially spaced projections on said shoulder and extending toward said large diameter end, four of said projections being positioned at 90 intervals from'each other, electrically conductive contact members mounted on at least four of said projections and extending' toward the center of said shell, each of said contact members having Wall structure forming pin-receiving slots extending parallel to the axis of the shell, each of said slots being located inwardly of the inner edge of said shoulder, and said projections and contact members being so spaced and dimensioned that fivecontact members is the maximum usable number. 7

' 2. Socket for electron tubes, comprising a tubular dielectric shell having a small diameter end and a large diameter end and an annular shoulder intermediate said ends, six circumferentially spaced projections on said shoulder and extending toward said large diameter end, four of said projections being positioned at 90 intervals from each other, electrically conductive contact members mounted on at least four of said projections and extending toward the center of said shell, each of said contact members having wall structure forming pin-receiving slots extending parallel to the axis of the shell, each of said slots being located inwardly of the inner edge of said shoulder adjacenteach of said contact members, an outwardly projecting mounting rim on said large diameter end of the shell, and said projections and contact members being so spaced and dimensioned that five contact members is the maximum usable number.

3. Socket for electron tubes, comprising a tubular shell having an inwardly projecting annular shoulder intermediate its ends, a plurality of projections on said shoulder extending toward one end of said shell, electrically conductive contact clips mounted on said projections, each of said clips comprising support arms straddling the projection on which it is mounted and projecting toward the center of said shell, Wall structure carried by said arms and forming for each contact clip a pin-receiving slot The remainingtwo projections 10 and 12 extending parallel to the axis of the shell, said support arms having a non-rigid fit with the projection they straddle, and means for holding said clips assembled on said socket, said arms on each clip being free to spread apart along their lengths and including the portions of their lengths which straddle their respective projections.

4. Socket for electron tubes, comprising a tubular shell having a small diameter end and a large diameter end and an annular step intermediate said ends, a plurality of projections on said step extending toward the large diameter end of said shell, electrically conductive contact clips mounted on said projections, each of said clips comprising a body strip projecting through said step to form a terminal post outside said shell, support arms on said body strip and straddling the projection on which the individual clip is mounted and Wall structure carried by said arms and forming for each contact clip a pin-receiving slot extending parallel to the axis of said shell, said arms on each clip being free to spread apart along their lengths and including the portions of their lengths which straddle their respective projections.

5. Socket for electron tubes, comprising a tubular shell having a small diameter end and a large diameter end and an annular step intermediate said ends, a plurality of projections on said step extending toward the large diameter end of said shell, electrically conductive contact clips mounted on said projections, each of said clips comprising a body strip projecting through said step to form a terminal post outside said shell, support arms on said body strip and stradding the projection on which the individual clip is mounted, wall structure carried by said arms and forming for each contact clip a pin-receiving slot extending parallel to the axis of said shell, and a back tab on each of said body strips projecting away from the center of said shell for engagement with the inner wall surface of said large diameter end of the shell.

6. Socket for electron tubes, comprising a tubular shell having a small diameter end and a large diameter end and an annular step intermediate said ends, a plurality of projections on said step extending toward the large diameter end of said shell, electrically conductive contact clips mounted on said projections, each of said clips comprising a body strip projecting through a slot in said step to form a terminal post outside said shell, support arms on each body strip projecting toward the center of the shell and straddling one of said projections, wall structure carried by said arms and forming for each clip a pin-receiving slot, a back tab on each of said body strips extending away from said support arms for engagement with the inner wall surface of said large diameter end of the shell, and a portion of each said body strip being deformed into engagement with the outside surface of said step to hold each clip in the shell.

7. A socket as claimed in claim 6, in which said large diameter end of the shell is provided with an aperture adjacent each of said back tabs, whereby electrical con tact can be made direct to said back tab inside said shell instead of to said terminal post.

-8. A socket as claimed in claim 6, in which a punchout area is provided in the large diameter end of said shell adjacent each of said back tabs, said punch-out area comprising a portion of the wall of the shell having a substantially thinner wall thickness than the surrounding portions of the wall of the shell.

9. A shell for an electron tube socket, said shell comprising a one-piece tubular dielectric member having a large diameter wall at one end and a small diameter wall at the other end and an annular step connecting said large and small diameter walls, a plurality of spaced projections on said step extending toward said large diameter end, said step having a slot therethrough adjacent each of said projections, said step slots extending generally parallel to the axis of said shell, a mounting rirn extending outwardly at the end of said large diameter wall, said large diameter wall having a slot there-through adjacent at least one of said projections, said wall slot being located at the junction of said large diameter Wall and said mounting rim, and said mounting rim having a recess in its inner periphcry communicating with said slot in the large diameter wall.

110. A shell for an electron tube socket, said shell comprising a one-piece tubular dielectric member having a large diameter wall at one end and a small diameter wall at the other end and an annular step connecting said large and small diameter walls, a plurality of spaced projections on said step extending toward said large diameter end, said step having a slot therethro-ugh adjacent each of said projections, said slots extending generally parallel to the axis of said shell, a mounting rim extending out wardly at the end of said large diameter wall, said large diameter wall having a thin-wall punch-out area adjacent at least one of said projections, and said thin-wall area being located at the junction of said large diameter wall and said mounting rim.

References Cited by the Examiner UNITED STATES PATENTS 1,495,701 5/24 McLean 339-425 1,85 2,334 4/ 32 Robinson 339-220 1,904,662 4/33 Benjamin 339'256 X 2,514,562 7/50 Stickney. 2,613,244 10/52 Del Camp 33917 2,674,724 4/54 lust 339256 X 2,793,353 5/57 Del Camp 339-258 X 2,944,240 7/60 Barber 339-66 2,966,651 12/60 Von Holtz .33914 FOREIGN PATENTS 149,753 1/ 5 3 Australia. 1,073,058 1/60 Germany.

256,260 '7 26 Great Britain.

361,056 11/31 Great Britain.

798,899 7/58 Great Britain.

OTHER REFERENCES Electronic Design (Advertisement of AMP Inc, appearing on page 25), May 24, 1961.

JOSEPH D. 'SEERS, Primary Examiner, THOMAS J. HICKEY, Examiner, 

2. SOCKET FOR ELECTRON TUBES, COMPRISING A TUBULAR DIELECTRIC SHELL HAVING A SMALL DIAMETER END AND A LARGE DIAMETER END AND AN ANNULAR SHOULDER INTERMEDIATE SAID ENDS, SIX CIRCUMFERENTIALLY SPACED PROJECTIONS ON SAID SHOULDER AND EXTENDING TOWARD SAID LARGE DIAMETER END, FOUR OF SAID PROJECTIONS BEING POSITIONED AT 90* INTERVALS FROM EACH OTHER, ELECTRICALLY CONDUCTIVE CONTACT MEMBERS MOUNTED ON AT LEAST FOUR OF SAID PROJECTIONS AND EXTENDING TOWARD THE CENTER OF SAID SHELL, EACH OF SAID CONTACT MEMBERS HAVING WALL STRUCTURE FORMING PIN-RECEIVING SLOTS EXTENDING PARALLEL TO THE AXIS OF THE SHELL, EACH OF SAID SLOTS BEING LOCATED INWARDLY OF THE INNER EDGE OF SAID SHOULDER ADJACENT EACH OF SAID CONTACT MEMBERS, AN OUTWARDLY PRO- 